Commodore Business Machines, Inc.

Bruce F Ahrens

David W DiOrio

Robert J Raible

Chaoynan E Yang

Programmable I/O (input/output) interface circuitry provides video and audio signals, needed for a video computer/game, to a commercial color television type display/monitor and may be implemented in HMOS, (H type metal oxide semiconductor) large-scale-integrated circuitry. The system architecture allows for reduced chip count, and improved reliability while providing adequate synchronization pulses, luminance level signals, chrominance phase shift signals, raster control and cursor control video and three independently controlled audio voices. A software selectable keyboard latch input, plural speed processing for faster operation when outside the active display area or during blanking, all system control signals necessary for system operation and 3 independently controlled interrupt generating timers are also provided.

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Phoenixville, PA, United States of America

Bruce F Ahrens